/**
 *  Copyright (C) 2008-2013  Telosys project org. ( http://www.telosys.org/ )
 *
 *  Licensed under the GNU LESSER GENERAL PUBLIC LICENSE, Version 3.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *          http://www.gnu.org/licenses/lgpl.html
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.telosys.common.output.error;

/**
 * Holds an error that occurs durring the XML response generation 
 * 
 * @author Laurent Guerin
 * @since 1.0.5
 *
 */
public abstract class OutputError
{
    private Throwable _exception = null ;
    
    private String    _sMessage  = null ;
    
    /**
     * Constructor 
     * @param exception
     */
    public OutputError( Throwable exception )
    {
        super();
        _exception = exception;
        _sMessage  = null ;
    }

    /**
     * Constructor 
     * @param message
     */
    public OutputError( String message )
    {
        super();
        _exception = null;
        _sMessage  = message;
    }
    
    /**
     * Returns the exception that causes the error (or null if no exception)
     * @return
     */
    public Throwable getException()
    {
        return _exception;
    }
    
    /**
     * Returns the specific message if set, else the exception message if any. <br>
     * 
     * @return the message or "" (never null)
     */
    public String getMessage()
    {
        if ( _sMessage != null )  // 1) Specific message ( has priority )
        {
            return _sMessage ;
        }
        if ( _exception != null )  // 2) Exception message ( if any )
        {
            String s = _exception.getMessage() ;
            if ( s != null ) return s ;
        }
        return "";
    }
    
}
